# 1991 Copenhagen Open – Singles

No defending champions were officially declared as the last edition dates back to 1976, which was won by Lars Elvstrøm.
Jonas Svensson won the title by defeating Anders Järryd 6–7$^{(5–7)}$, 6–2, 6–2 in the final.

## Seeds

* Jonas Svensson (champion)
* Andrei Chesnokov (second round)
* Jakob Hlasek (semifinals)
* Karel Nováček (quarterfinals)
* Ronald Agénor (second round)
* Todd Woodbridge (semifinals)
* Christian Bergström (quarterfinals)
* Anders Järryd (final)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final |
| 1 | Jonas Svensson | 6 | 1 | 6 | | | | | |
| 3 | Jakob Hlasek | 2 | 6 | 3 | | | | | |
| 3 | Jakob Hlasek | 2 | 6 | 3 | 1 | Jonas Svensson | 6$^5$ | 6 | 6 |
| | | | | | 8 | Anders Järryd | 7$^7$ | 2 | 2 |
| 6 | Todd Woodbridge | 0 | 4 | | 8 | Anders Järryd | 7$^7$ | 2 | 2 |
| 8 | Anders Järryd | 6 | 6 | | | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | J Svensson | 7$^7$ | 6 | | | | | | | | | | | | | | | | |
| | M Střelba | 6$^3$ | 2 | | 1 | J Svensson | 6 | 2 | 6 | | | | | | | | | | |
| | E Masso | 6 | 3 | 2 | WC | F Fetterlein | 3 | 6 | 2 | | | | | | | | | | |
| WC | F Fetterlein | 3 | 6 | 6 | | | | | | 1 | J Svensson | 6 | 7 | | | | | | |
| | CU Steeb | 3 | 6 | 7 | | | | | | 7 | C Bergström | 4 | 5 | | | | | | |
| | H Holm | 6 | 3 | 5 | | CU Steeb | 6 | 3 | 3 | | | | | | | | | | |
| | J Eltingh | 3 | 5 | | 7 | C Bergström | 3 | 6 | 6 | | | | | | | | | | |
| 7 | C Bergström | 6 | 7 | | | | | | | | | | | | 1 | J Svensson | 6 | 1 | 6 |
| 3 | J Hlasek | 2 | 6 | 6 | | | | | | | | | | | 3 | J Hlasek | 2 | 6 | 3 |
| Q | M Zoecke | 6 | 4 | 3 | 3 | J Hlasek | 6 | 6 | | | | | | | | | | | |
| | L Jönsson | 6 | 6 | | | L Jönsson | 3 | 4 | | | | | | | | | | | |
| | L Herrera | 1 | 0 | | | | | | | 3 | J Hlasek | 3 | 6 | 6 | | | | | |
| Q | S Saceanu | 6 | 6 | | | | | | | Q | S Saceanu | 6 | 4 | 4 | | | | | |
| | M Tauson | 1 | 2 | | Q | S Saceanu | 6 | 7$^8$ | | | | | | | | | | | |
| | A Antonitsch | 6 | 3 | 4 | 5/WC | R Agénor | 3 | 6$^6$ | | | | | | | | | | | |
| 5/WC | R Agénor | 4 | 6 | 6 | | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 6 | T Woodbridge | 6 | 7 | | | | | | | | | | | | | | | |
| Q | P Henricsson | 2 | 5 | | 6 | T Woodbridge | 6 | 6 | | | | | | | | | | |
| | S Pescosolido | 4 | 5 | | | T Högstedt | 3 | 0 | | | | | | | | | | |
| | T Högstedt | 6 | 7 | | | | | | | 6 | T Woodbridge | 7$^7$ | 4 | 6 | | | | |
| Q | A Olhovskiy | 6$^2$ | 6 | 4 | | | | | | 4 | K Nováček | 6$^1$ | 6 | 1 | | | | |
| | JF Altur | 7$^7$ | 2 | 6 | | JF Altur | 3 | 2 | | | | | | | | | | |
| WC | T Enqvist | 2 | 6 | 4 | 4 | K Nováček | 6 | 6 | | | | | | | | | | |
| 4 | K Nováček | 6 | 3 | 6 | | | | | | | | | | | 6 | T Woodbridge | 0 | 4 |
| 8 | A Järryd | 6 | 6 | | | | | | | | | | | | 8 | A Järryd | 6 | 6 |
| | B Wuyts | 3 | 2 | | 8 | A Järryd | 6 | 6 | | | | | | | | | | |
| | J Gunnarsson | 6 | 6 | | | J Gunnarsson | 3 | 2 | | | | | | | | | | |
| | P Kühnen | 3 | 2 | | | | | | | 8 | A Järryd | 6 | 6 | | | | | |
| | J Wöhrmann | 6 | 1 | 4 | | | | | | | M Woodforde | 1 | 3 | | | | | |
| | M Woodforde | 2 | 6 | 6 | | M Woodforde | 6 | 2 | 7$^7$ | | | | | | | | | |
| | P Baur | 6 | 2 | 4 | 2 | A Chesnokov | 2 | 6 | 6$^2$ | | | | | | | | | |
| 2 | A Chesnokov | 4 | 6 | 6 | | | | | | | | | | | | | | |